The invention relates to a collapsible-boxes gluing machine for producing collapsible boxes from blanks, with a device for transporting the blanks through the machine, whereby the device comprises lower conveyor belts supported on a roller cheek transversely movable by means of a drive and upper conveyor belts, which are also supported on a roller rail which is mounted so as to be transversely movable.
As is known, collapsible-box gluing machines can produce collapsible boxes from blanks in several processing stations, which are successively traversed by the blanks/boxes.
First the blanks are picked up one after the other from a stack in a high-speed feeder and fed individually directly to a folding station or, initially, to a so-called preliminary crusher, which precedes the folding station. In the folding station the blank parts provided with a glue strip are turned over by 180xc2x0, i.e. folded, for the purpose of producing an adhesive connection. In the preliminary crusher the folding flaps are folded back and forth prior to the application of the adhesive, so that the corresponding longitudinal groove lines are softened and made more pliant.
The folding station is normally followed by a so-called transfer station, where the boxes can be counted, marked andxe2x80x94if defectivexe2x80x94thrown out. Then follows a collection and compression device, wherein at first a stream of folded overlapping blanks is formed, which subsequently is kept under pressure for a while between compression belts, so that the two blank parts are connected at the gluing seam. The final stage is usually a packaging device, where the flat, folded collapsible boxes are packaged in cartons.
The transport of the blanks through the individual processing stations takes place by means of upper and lower conveyor belts, each supported on their sides facing away from the blanks, As a rule over the machine width two pairs of narrow belts are used, which for the adjustment to various box formats, can be shifted transversely for the optimal contact line with the blanks. As is known, the upper conveyor belts can be lifted with their mounting, so that when the machine jams, the boxes can be removed.
It is known to divide the conveyor path into individual segments. Each of the lower transport belts of a segment is supported in a so-called roller cheek which extends over the desired conveyor path, and comprises at its upper side over its length a row of narrow rollers, which support the upper strand of the conveyor belt on its underside. Each upper conveyor belt of a segment is supported on a so-called roller rail, which also extends in transport direction over the desired conveyor path and has at its underside a row of rollers, which support the upper side of the lower belt strand. Roller cheeks and roller rails can each be positioned transversely, so that they are arranged directly one above the other in the desired work position, in order to hold and transport the blanks between the conveying belt strands. At least the conveyor belts of the roller cheeks arranged at the bottom are driven. The conveyor belts of the pertaining top roller rails are either idlers orxe2x80x94for instance when processing thick blanks or corrugated cardboardxe2x80x94are also driven in order to avoid marking of the blanks.
In the known collapsible-box gluing machines, the parts on which the upper roller rails are fastened are of a complicated construction, so that they can be synchronously transversely positioned with the pertaining roller cheek and lifted at the same time.
It is therefore the object of the invention to simplify the construction of a generic collapsible-boxes gluing machine. This object is achieved in a collapsible-boxes gluing machine for producing collapsible boxes from blanks with a device for the transport of the blanks through the machine, comprising:
lower conveyor belts, which are supported on a roller cheek
transversely displaceable by means of a drive; and
upper conveyor belts which are supported on a transversely displaceable roller rail. An endless cable or belt-like element, preferably a wire cable, is arranged in the machine in double strands freely movable in its longitudinal direction, so that
a loop runs below the conveying plane of the blanks across the machine width and
a second loop runs parallel to the first loop above the conveying plane across the machine width. The roller cheek is rigidly connected with a strand of the lower loop and the roller rail can be securely clamped to the other strand of the upper loop, so that the roller rail is entrained during a transverse displacement of the roller cheek.
In preferred, particularly advantageous embodiments of the invention, the upper loop runs above the roller rail.
On each side of the machine there are stands, a support beam being supported between the stands at a distance above the conveying plane, whereby the roller rail is fastened to the lower end of the support part, which at its upper end is designed as a travelling carriage suspended from the support beam. The upper loop of the belt or cable-like element runs above the support beam. The support beam is supported so as to be vertically movable on the stands.